Method and apparatus for data stackification for run-to-run control

ABSTRACT

In one embodiment, a method and apparatus is provided for data stackification for run-to-run control. A process run of semiconductor devices is processed. A manufacturing tag associated with the process run of semiconductor devices is recorded. Metrology data relating to the processed semiconductor devices is then acquired. The present invention calls for performing a metrology data stackification process upon the metrology data using the manufacturing tag for organizing and stacking the metrology data. The present invention provides for modifying at least one control parameter based upon the stacked metrology data.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to semiconductor productsmanufacturing, and, more particularly, to a method and apparatus forperforming data stacking in an orderly manner for efficient run-to-runcontrol in manufacturing of semiconductor devices.

2. Description of the Related Art

The technology explosion in the manufacturing industry has resulted inmany new and innovative manufacturing processes. Today's manufacturingprocesses, particularly semiconductor manufacturing processes, call fora large number of important steps. These process steps are usuallyvital, and therefore, require a number of inputs that are generallyfine-tuned to maintain proper manufacturing control.

The manufacture of semiconductor devices requires a number of discreteprocess steps to create a packaged semiconductor device from rawsemiconductor material. The various processes, from the initial growthof the semiconductor material, the slicing of the semiconductor crystalinto individual wafers, the fabrication stages (etching, doping, ionimplanting, or the like), to the packaging and final testing of thecompleted device, are so different from one another and specialized thatthe processes may be performed in different manufacturing locations thatcontain different control schemes.

Among the important aspects in semiconductor device manufacturing areRTA control, chemical-mechanical (CMT) control, etching, and overlaycontrol. Overlay is one of several important steps in thephotolithography area of semiconductor manufacturing. Overlay processinvolves measuring the misalignment between two successive patternedlayers on the surface of a semiconductor device. Generally, minimizationof misalignment errors is important to ensure that the multiple layersof the semiconductor devices are connected and functional. Generally,after the photolithography process is performed on a semiconductordevice, an etch process is performed on the semiconductor device forforming a plurality of subsections within a semiconductor device, suchas a gate. As technology facilitates smaller critical dimensions forsemiconductor devices, the need for reduced of errors increasesdramatically.

Generally, process engineers currently analyze the process errors a fewtimes a month. The results from the analysis of the process errors areused to make updates to process tool settings manually. Generally, amanufacturing model is employed to control the manufacturing processes.Some of the problems associated with the current methods include thefact that the process tool settings are only updated a few times amonth. Furthermore, currently the process tool updates are generallyperformed manually. Many times, errors in semiconductor manufacturingare not organized and reported to quality control personal. Often, themanufacturing models themselves incur bias errors that could compromisemanufacturing quality.

Generally, a set of processing steps is performed on a lot of wafers ona semiconductor manufacturing tool called an exposure tool or a stepper,followed by processing of the semiconductor wafers in etch tools. Themanufacturing tool communicates with a manufacturing framework or anetwork of processing modules. The manufacturing tool is generallyconnected to an equipment interface. The equipment interface isconnected to a machine interface to which the stepper is connected,thereby facilitating communications between the stepper and themanufacturing framework. The machine interface can generally be part ofan advanced process control (APC) system. The APC system initiates acontrol script based upon a manufacturing model, which can be a softwareprogram that automatically retrieves the data needed to execute amanufacturing process. Often, semiconductor devices are staged throughmultiple manufacturing tools for multiple processes, generating datarelating to the quality of the processed semiconductor devices. Manytimes, errors can occur during the processing of semiconductor devices.Furthermore, manufacturing data that is often acquired in differentsequences resulting in data sets that are out of order. Manufacturingdata sets that are out of order causes additional difficulties insorting through manufacturing errors and correcting them.

The present invention is directed to overcoming, or at least reducingthe effects of, one or more of the problems set forth above.

SUMMARY OF THE INVENTION

In one aspect of the present invention, a method is provided fororganizing production data. At least one process run of semiconductordevices is performed. At least one manufacturing tag associated with theprocess run of semiconductor devices is recorded. Metrology upon atleast one of the process run of semiconductor device is performed foracquiring metrology data. A metrology data stackification process isperformed upon the metrology data using the manufacturing tag fororganizing and stacking the metrology data. At least one controlparameter is modified based upon the stacked metrology data.

In another aspect of the present invention, an apparatus is provided fororganizing production data. The apparatus of the present inventioncomprises: a processing tool for processing a production run ofsemiconductor wafers; a metrology tool coupled with the processing tooland being capable of acquiring metrology data relating to the processedsemiconductor wafers; a metrology data stacking unit coupled with themetrology tool and being capable of stacking the metrology data; acomputer system coupled with the metrology data stacking unit and beingcapable of controlling directing and storing metrology databi-directionally to and from the metrology data stacking unit; a controlparameter filter unit coupled with the computer system and being capableof filtering data from the metrology data stacking unit; and amanufacturing model coupled with the computer system and the processingtool, the manufacturing model being capable of modifying controlparameters in response to the filtering data from the metrology datastacking unit, for controlling the processing tool.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be understood by reference to the followingdescription taken in conjunction with the accompanying drawings, inwhich like reference numerals identify like elements, and in which:

FIG. 1 illustrates one embodiment of the present invention;

FIG. 2 illustrates a flowchart representation of one method oforganizing manufacturing data and correcting manufacturing errors, astaught by the present invention;

FIG. 3 illustrates a more detailed depiction of the step of performingmanufacturing data stackification described in FIG. 2;

FIG. 4 illustrates a flowchart representation of a more detaileddepiction of the method of filtering manufacturing data described inFIG. 3; and

FIG. 5 illustrates the dependence of the average on each successivepoint in an Exponentially-Weighted Moving Average (EWMA) filter.

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof have been shown by wayof example in the drawings and are herein described in detail. It shouldbe understood, however, that the description herein of specificembodiments is not intended to limit the invention to the particularforms disclosed, but on the contrary, the intention is to cover allmodifications, equivalents, and alternatives falling within the spiritand scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

Illustrative embodiments of the invention are described below. In theinterest of clarity, not all features of an actual implementation aredescribed in this specification. It will of course be appreciated thatin the development of any such actual embodiment, numerousimplementation-specific decisions must be made to achieve thedevelopers' specific goals, such as compliance with system-related andbusiness-related constraints, which will vary from one implementation toanother. Moreover, it will be appreciated that such a development effortmight be complex and time-consuming, but would nevertheless be a routineundertaking for those of ordinary skill in the art having the benefit ofthis disclosure.

There are many discrete processes that are involved in semiconductormanufacturing. Many times, semiconductor devices are stepped throughmultiple manufacturing process tools. As semiconductor devices areprocessed through manufacturing tools, production data, or manufacturingdata, is generated. The production data can be used to perform faultdetection analysis that can lead to improved manufacturing results.Overlay and etching processes are important groups of process steps insemiconductor manufacturing. In particular, metrology data, includingmanufacturing data, is acquired after manufacturing processes such asphotolithography and photoresist etching processes are substantiallycompleted. The metrology data can be used to make adjustments tomanufacturing processes for subsequent manufacturing runs ofsemiconductor devices, such as semiconductor wafers. Proper organizationand retrieval of metrology data is important in making adjustments tosubsequent manufacturing processes. Many times, a plurality ofmanufacturing lots of semiconductor wafers is processed and metrologydata relating to each of the manufacturing lots are acquired out oforder. Often, measurement processes of some manufacturing lots areomitted and other times, only part of a production line is examined.This could result in incomplete or out of sequence metrology data, whichcould cause inefficiencies in filtering the metrology data andperforming corrections based upon the filtered data. The presentinvention provides a method and apparatus for organizing metrology dataand efficiently filtering the metrology data and performing adjustmenton a run-to-run control basis.

Turning now to FIG. 1, one embodiment of the present invention isillustrated. In one embodiment, semiconductor products 105, such assemiconductor wafers are processed on processing tools 110, 112 using aplurality of control input signals on a line 120. In one embodiment, thecontrol input signals on the line 120 are sent to the processing tools110, 112 from a computer system 130 via machine interfaces 115, 117. Inone embodiment, the first and second machine interfaces 115, 117 arelocated outside the processing tools 110, 112. In an alternativeembodiment, the first and second machine interfaces 115, 117 are locatedwithin the processing tools 110, 112.

In one embodiment, the computer system 130 sends control input signalson a line 120 to the first and second machine interfaces 115, 117. Thecomputer system 130 employs a manufacturing model 140 to generate thecontrol input signals on the line 120. A control parameter filter unit135, which in one embodiment is a computer software program, is utilizedby the computer system 130 to control the manufacturing processesperformed by the processing tools 110, 112. In one embodiment, thecontrol parameter filter unit 135 is integrated into the computer system130. In one embodiment, the control parameter filter unit 135 is capableof performing EWMA filtering upon the metrology data and generating andmodifying at least one control input signal, on the line 120, thatcontrols the semiconductor manufacturing operations performed by theprocessing tools A and B 110, 112.

In one embodiment, the control parameter filtering unit 135 filters andprocesses data that is organized by the metrology data-stacking unit145. In one embodiment, the metrology data-stacking unit 145 comprises acomputer software program and a data storage device. The metrologydata-stacking unit 145 acquires metrology data from a metrology tool 150on a line 155 and organizes and stacks the acquired metrology data. Thecomputer system 130 then accesses the metrology data and sends themetrology data to the control parameter filtering unit 135. In oneembodiment, the metrology data-stacking unit 145 is integrated into thecomputer system 130.

In one embodiment, the manufacturing model 140 defines a process scriptand input control that implement a particular manufacturing process. Thecontrol input signals on a line 120 that are intended for processingtool A 110 are received and processed by the first machine interface115. The control input signals on a line 120 that are intended forprocessing tool B 112 are received and processed by the second machineinterface 117. Examples of the processing tools 110, 112 used insemiconductor manufacturing processes are steppers and etch processtools. In one embodiment, processing tool A 110 is a standard etchprocess tool and processing tool B 112 is a secondary etch process tool.

For processing tools such as steppers, the control inputs, on the line120, that are used to operate the processing tools 110, 112 include anx-translation signal, a y-translation signal, an x-expansion wafer scalesignal, a y-expansion wafer scale signal, a reticle magnificationsignal, and a reticle rotation signal. Generally, errors associated withthe reticle magnification signal and the reticle rotation signal relateto one particular exposure process on the surface of the wafer beingprocessed in the exposure tool. For processing tools such as etchprocess tools, the control inputs on the line 120 include an etchtime-period control signal, an etch temperature control signal, and anetch pressure control signal.

For photolithography processes, when a process step in a processing tool110, 112 is concluded, the semiconductor product 105 or wafer that isbeing processed is examined in a review station. One such review stationis a KLA review station. One set of data derived from the operation ofthe review station is a quantitative measure of the amount ofmisregistration that was caused by the previous exposure process. In oneembodiment, the amount of misregistration relates to the misalignment inthe process that occurred between two layers of a semiconductor wafer.In one embodiment, the amount of misregistration that occurred can beattributed to the control inputs for a particular exposure process. Thecontrol inputs generally affect the accuracy of the process stepsperformed by the processing tools 110, 112 on the semiconductor wafer.Modifications of the control inputs can be utilized to improve theperformance of the process steps employed in the manufacturing tool.Many times, the errors that are found in the processed semiconductorproducts 105 can be correlated to a particular fault analysis andcorrective actions can be taken to reduce the errors.

Turning now to FIG. 2, a flow chart representation of one method ofperforming stacking and filtering of production data is illustrated. Atleast one production run of semiconductor devices, such as semiconductorwafers, is processed, as described in block 210 of FIG. 2. In oneembodiment, a photolithography process is performed on the semiconductorwafers. However, it is understood that other semiconductor manufacturingprocesses that are known by those skilled in the art can be implementedby methods and apparatus taught by the present invention.

After at least one production run of semiconductor wafers is processed,a corresponding time stamp associated with the time and date of theproduction run is recorded for later retrieval, as described in block220 of FIG. 2. In one embodiment, the time stamp is stored in the memory(not shown) of the computer system 130. In one embodiment, the computersystem 130 is integrated with a process control system, such as the APCframework. Furthermore, a lot number associated with the production runof semiconductor wafers is also recorded for later retrieval, asdescribed in block 230 of FIG. 2. In one embodiment, the lot number isstored in the memory of the computer system 130.

Once the time stamp and lot number associated with a production run ofprocessed semiconductor wafers are recorded, metrology is performed onthe production run of processed semiconductor wafers, as described inblock 240 of FIG. 2. In one embodiment, metrology is performed on theprocessed semiconductor wafers using the metrology tool 150. Metrologydata from the metrology tool 150 is extracted by the computer system 130and sent to the metrology data-stacking unit 145 via the line 155. Oncemetrology data is acquired, metrology data stackification process isperformed, as described in block 250 of FIG. 2. A more detaileddepiction of the steps for performing metrology data stackificationprocess is illustrated in FIG. 3.

Turning now to FIG. 3, the recorded time stamp data and the lot numberdata that are associated with a particular production run ofsemiconductor wafers from which the metrology data was acquired, areextracted from storage and correlated with the metrology data, asdescribed in block 310 of FIG. 3. Once the time stamp and the lot numberare correlated with a particular set of metrology data, an order fororganizing the metrology data and its corresponding time stamp and lotnumber data, is determined, as described in block 320 of FIG. 3. In oneembodiment, the metrology data stacking unit 145 generates the order fororganizing the metrology data. In one embodiment, the metrology data isorganized in chronological order with respect to the time stampassociated with a particular run of semiconductor wafers from which themetrology data was acquired. In an alternative embodiment, the metrologydata is organized in a numerical order with respect to the lot numberassociated with a particular run of semiconductor wafers from which themetrology data was acquired. Other manufacturing tagging data known bythose skilled in the art can be employed to generate an order fororganizing the metrology data.

When the order for the organization of metrology data is determined, themetrology data is stacked in that order, as described in block 330 ofFIG. 3. In one embodiment, the metrology data is stacked in memorywithin the metrology data stacking unit 145. The metrology is then readyto be retrieved and used for analysis to correct errors in subsequentproduction run of semiconductor wafers. In order to properly process thestacked metrology data, the metrology data is generally filtered toreduce noise and other data errors within the stacked metrology data.Therefore, a data filtering process is employed on the data stored inthe metrology data stack unit 145. A more detailed depiction of thesteps for performing filtering of data stored in the metrology datastacking unit 145 is illustrated in FIG. 4. In one embodiment, anExponentially-Weighted Moving Average (EWMA) filtering process isemployed to filter the stacked data in the metrology data stacking unit145.

Turning now to FIG. 4, a determination is made regarding whichparticular manufacturing parameter within the stacked data in themetrology data stacking unit 145 is to be filtered, as described inblock 410. An average value is calculated for the particularmanufacturing parameter to be filtered, as described in block 420 ofFIG. 4. Once an average value of a particular manufacturing parameter isdetermined, the average value is used as an initial point for the EWMAcalculations, as described in block 430 of FIG. 4. When the initialpoint for the EWMA calculation is determined, the EWMA filtering processis performed on the manufacturing parameter stored in the metrology datastacking unit 145, as described in block 440 of FIG. 4. One embodimentof employing the EWMA filtering process is described below.

The EWMA filtering process is used to smooth out the data stored in themetrology data stacking unit. This is important because the errormeasurements are subject to a certain amount of randomness, such thatthe error significantly deviates in value. Filtering the stacked dataresults in a more accurate assessment of the error in the control inputsignal settings used to control the semiconductor manufacturingprocesses performed by the processing tool A and B 110, 112. In oneembodiment, the overlay control scheme generally utilizes the EWMAfilter, although other filtering procedures can be utilized in thiscontext. The equation for the EWMA filter is illustrated in Equation 1.

New average=(weight)*(current measurement)+(1−weight)*(previous EWMAaverage)]  Equation 1

The weight is an adjustable parameter that can be used to control theamount of filtering and is generally between zero and one. The weightrepresents the confidence in the accuracy of the current data point. Ifthe measurement is considered to be accurate, the weight should be closeto one. If there were a significant amount of fluctuations in theprocess, then a number closer to zero would be appropriate. The newaverage is calculated from the current measurement, the weight, and thelast average calculated. The dependence of the average on eachsuccessive point is illustrated in FIG. 5.

In one embodiment, there are at least two methods of utilizing the EWMAfiltering process. The first implementation is to use the previousaverage, the weight, and the current measurement as described above.Among the advantages of utilizing the first implementation are ease ofuse and minimal data storage. One of the disadvantages of utilizing thefirst implementation is that this method generally does not retain muchprocess information. Furthermore, the previous average calculated inthis manner would be made up of every data point that preceded it, whichmay be undesirable. The second option is to retain only some of the dataand calculate the average from the raw data each time.

The manufacturing environment in the semiconductor manufacturing fabpresents some unique challenges. The order that the semiconductor waferlots are processed through a semiconductor manufacturing tool, such as astepper, may not correspond to the order in which they are read on thereview station. This could lead to the data points being added to theEWMA average out of sequence. Semiconductor wafer lots may be analyzedmore than once to verify the error measurements. With no data retention,both readings would contribute to the EWMA average, which may be anundesirable characteristic. Furthermore, some of the control threads mayhave low volume, which may cause the previous average to be outdatedsuch that it may not be able to accurately represent the error in thecontrol input signal settings. Furthermore, it may not be desirable toretain all historical process data since the disk storage space within acontrol database may be limited. Older process data may be discardedwithout causing a significant change in the EWMA estimate, as therelative weight on older data diminishes in the EWMA calculations.

For the reasons discussed above, and for other considerations known bythose skilled in the art, the overlay controller uses limited storage ofdata to calculate the EWMA filtered error. Semiconductor wafer lot data,including the lot number, the time the lot was processed on thesemiconductor manufacturing tool, such as the stepper, and the multipleerror estimates, are stored in a data storage (called Data Store [notshown] in one embodiment) under a control thread name. When a new set ofdata is collected, the stack of data is retrieved from Data Store andanalyzed. The lot number of the current semiconductor wafer lot beingprocessed is compared to those in the stack. If the lot number matchesany of the data present there, the error measurements are replaced.Otherwise, the data point is added to the current stack in chronologicalorder, according to the time periods when the lots were processedthrough the stepper. In one embodiment, any data point within the stackthat is over 120 hours old is removed. Once the aforementioned steps arecomplete, the new filter average is calculated and stored to Data Store.

Referring back to block 350 of FIG. 3, once the EWMA filtering processis completed, new calculations for the control inputs for semiconductormanufacturing processes, based upon the filtered data are determined,which substantially concludes the metrology data stackification processdescribed in block 240 of FIG. 2. The new calculation for the controlinputs are performed by one of a number of control input modificationsequences that are known by those skilled in the art. Turning back toFIG. 2, once the new calculations for new control input parameters aredetermined, the control input parameters are modified for use in asubsequent production run of semiconductor wafers, as described in block260 of FIG. 2. The modified control inputs are implemented into themanufacturing model 140, reducing errors during subsequent productionruns of semiconductor wafers. In one embodiment, the control inputs aremodified on a run-to-run basis.

The principles taught by the present invention can be implemented in anAdvanced Process Control (APC) Framework. The APC is a preferredplatform from which to implement the overlay control and etch processcontrol strategy taught by the present invention. In some embodiments,the APC can be a factory-wide software system, therefore, the controlstrategies taught by the present invention can be applied to virtuallyany of the semiconductor manufacturing tools on the factory floor. TheAPC framework also allows for remote access and monitoring of theprocess performance. Furthermore, by utilizing the APC framework, datastorage can be more convenient, more flexible, and less expensive thanlocal drives. The APC platform allows for more sophisticated types ofcontrol because it provides a significant amount of flexibility inwriting the necessary software code.

Deployment of the control strategy taught by the present invention ontothe APC framework could require a number of software components. Inaddition to components within the APC framework, a computer script iswritten for each of the semiconductor manufacturing tools involved inthe control system. When a semiconductor manufacturing tool in thecontrol system is started in the semiconductor manufacturing fab, itgenerally calls upon a script to initiate the action that is required bythe process controller, such as the overlay controller and etch processcontroller. The control methods are generally defined and performed inthese scripts. The development of these scripts can comprise asignificant portion of the development of a control system.

The particular embodiments disclosed above are illustrative only, as theinvention may be modified and practiced in different but equivalentmanners apparent to those skilled in the art having the benefit of theteachings herein. Furthermore, no limitations are intended to thedetails of construction or design herein shown, other than as describedin the claims below. It is therefore evident that the particularembodiments disclosed above may be altered or modified and all suchvariations are considered within the scope and spirit of the invention.Accordingly, the protection sought herein is as set forth in the claimsbelow.

What is claimed:
 1. A method, comprising: performing at least oneprocess run of semiconductor devices; recording at least onemanufacturing tag associated with said process run of semiconductordevices; performing metrology upon at least one said process run ofsemiconductor device for acquiring metrology data; performing ametrology data stackification process upon said metrology data usingsaid manufacturing tag for organizing and stacking said metrology data;and modifying at least one control parameter based upon said stackedmetrology data.
 2. The method described in claim 1, wherein recording atleast one manufacturing tag associated with said process run ofsemiconductor devices further comprises recording a time stampassociated with said process run of semiconductor devices.
 3. The methoddescribed in claim 1, wherein recording at least one manufacturing tagassociated with said process run of semiconductor devices furthercomprises recording a lot number associated with said process run ofsemiconductor devices.
 4. The method described in claim 1, whereinperforming a process run of semiconductor devices further comprisesprocessing semiconductor wafers.
 5. The method described in claim 4,wherein processing semiconductor wafers further comprises performing aphotoresist etching process on said semiconductor wafers.
 6. The methoddescribed in claim 4, wherein processing semiconductor wafers furthercomprises performing a photolithography process on said semiconductorwafers.
 7. The method described in claim 1, wherein performing ametrology data stackification process upon said metrology data furthercomprises: correlating said metrology data to at least one of acorresponding lot number and a corresponding time stamp of saidproduction run of semiconductor devices; determining an order fororganizing said metrology data based upon said correlation of saidmetrology data; stacking said metrology data based upon said order fororganizing said metrology data for creating stacked data; filtering saidstacked data for generating filtered stacked data; and calculatingmodified values for at least one control input parameter based upon saidfiltered stacked data.
 8. The method described in claim 7, whereindetermining an order for organizing said metrology data furthercomprises determining a chronological order in relation to said timestamp for organizing said metrology data.
 9. The method described inclaim 8, wherein stacking said metrology data further comprises storingsaid metrology data in a chronological sequence in relation to said timestamp.
 10. The method described in claim 7, wherein determining an orderfor organizing said metrology data further comprises determining anumerical order in relation to said lot number for organizing saidmetrology data.
 11. The method described in claim 10, wherein stackingsaid metrology data further comprises storing said metrology data in anumerical sequence in relation to said lot number.
 12. The methoddescribed in claim 7, wherein filtering said stacked data for generatingfiltered stacked data further comprises: determining a manufacturingparameter within the stacked data to be filtered; calculating an averagevalue of said manufacturing parameter; using said average value as aninitial point for performing filtering; and performing filtering uponsaid manufacturing parameter using said initial point.
 13. The methoddescribed in claim 12, wherein performing filtering upon saidmanufacturing parameter further comprises performing an ExponentiallyWeighted Moving Average (EWMA) calculation.
 14. An apparatus,comprising: a processing tool for processing a production run ofsemiconductor wafers; a metrology tool coupled with said processing tooland being capable of acquiring metrology data relating to said processedsemiconductor wafers; a metrology data stacking unit coupled with saidmetrology tool and being capable of stacking said metrology data; acomputer system coupled with said metrology data stacking unit and beingcapable of controlling directing and storing metrology databi-directionally to and from said metrology data stacking unit; acontrol parameter filter unit coupled with said computer system andbeing capable of filtering data from said metrology data stacking unit;and a manufacturing model coupled with said computer system and saidprocessing tool, said manufacturing model being capable of modifyingcontrol parameters in response to said filtering data from saidmetrology data stacking unit, for controlling said processing tool. 15.The apparatus of claim 14, wherein said processing tool is capable ofperforming photolithography manufacturing operation upon at least onesemiconductor wafer.
 16. The apparatus of claim 14, wherein metrologydata stacking unit further comprises a data ordering algorithm and adata storage unit.
 17. The apparatus of claim 14, wherein controlparameter filter unit is capable of performing Exponential WeightedMoving Average filtering processes.
 18. A system, comprising: means forperforming at least one process run of semiconductor devices; means forrecording a time stamp associated with said process run of semiconductordevices; means for recording a lot number associated with said processrun of semiconductor devices; means for performing metrology upon atleast one said process run of semiconductor device for acquiringmetrology data; means for performing a metrology data stackificationprocess upon said metrology data using said recorded time stamp and saidlot number for organizing and stacking said metrology data; and meansfor modifying at least one control parameter based upon said stackedmetrology data.
 19. The computer readable program storage device encodedwith instructions that, when executed by a computer, performs the methoddescribed in claim 18, wherein recording at least one manufacturing tagassociated with said process run of semiconductor devices furthercomprises recording a time stamp associated with said process run ofsemiconductor devices.
 20. The computer readable program storage deviceencoded with instructions that, when executed by a computer, performsthe method described in claim 18, wherein recording at least onemanufacturing tag associated with said process run of semiconductordevices further comprises recording a lot number associated with saidprocess run of semiconductor devices.
 21. The computer readable programstorage device encoded with instructions that, when executed by acomputer, performs the method described in claim 18, wherein performinga process run of semiconductor devices further comprises processingsemiconductor wafers.
 22. The computer readable program storage deviceencoded with instructions that, when executed by a computer, performsthe method described in claim 21, wherein processing semiconductorwafers further comprises performing a photoresist etching process onsaid semiconductor wafers.
 23. The computer readable program storagedevice encoded with instructions that, when executed by a computer,performs the method described in claim 21, wherein processingsemiconductor wafers further comprises performing a photolithographyprocess on said semiconductor wafers.
 24. The computer readable programstorage device encoded with instructions that, when executed by acomputer, performs the method described in claim 18, wherein performinga metrology data stackification process upon said metrology data furthercomprises: correlating said metrology data to at least one of acorresponding lot number and a corresponding time stamp of saidproduction run of semiconductor devices; determining an order fororganizing said metrology data based upon said correlation of saidmetrology data; stacking said metrology data based upon said order fororganizing said metrology data for creating stacked data; filtering saidstacked data for generating filtered stacked data; and calculatingmodified values for at least one control input parameter based upon saidfiltered stacked data.
 25. The computer readable program storage deviceencoded with instructions that, when executed by a computer, performsthe method described in claim 24, wherein determining an order fororganizing said metrology data further comprises determining achronological order in relation to said time stamp for organizing saidmetrology data.
 26. The computer readable program storage device encodedwith instructions that, when executed by a computer, performs the methoddescribed in claim 25, wherein stacking said metrology data furthercomprises storing said metrology data in a chronological sequence inrelation to said time stamp.
 27. The computer readable program storagedevice encoded with instructions that, when executed by a computer,performs the method described in claim 24, wherein determining an orderfor organizing said metrology data further comprises determining anumerical order in relation to said lot number for organizing saidmetrology data.
 28. The computer readable program storage device encodedwith instructions that, when executed by a computer, performs the methoddescribed in claim 27, wherein stacking said metrology data furthercomprises storing said metrology data in a numerical sequence inrelation to said lot number.
 29. The computer readable program storagedevice encoded with instructions that, when executed by a computer,performs the method described in claim 24, wherein filtering saidstacked data for generating filtered stacked data further comprises:determining a manufacturing parameter within the stacked data to befiltered; calculating an average value of said manufacturing parameter;using said average value as an initial point for performing filtering;and performing filtering upon said manufacturing parameter using saidinitial point.
 30. The computer readable program storage device encodedwith instructions that, when executed by a computer, performs the methoddescribed in claim 29, wherein performing filtering upon saidmanufacturing parameter further comprises performing an ExponentiallyWeighted Moving Average (EWMA) calculation.
 31. A computer readableprogram storage device encoded with instructions that, when executed bya computer, performs a method, comprising: performing at least oneprocess run of semiconductor devices; recording at least onemanufacturing tag associated with said process run of semiconductordevices; performing metrology upon at least one said process run ofsemiconductor device for acquiring metrology data; performing ametrology data stackification process upon said metrology data usingsaid manufacturing tag for organizing and stacking said metrology data;and modifying at least one control parameter based upon said stackedmetrology data.